Ingot mold



Patented ee EMIL GATI-TMANN, 03E BALTIMORE, MARYLAND.

. INGOT MOLD.

Application filed November 9, 1925. Serial No. 617%..

This invention relates to certain improvements in the construction of ingot molds of the kind described in my U. S. Patent No. 1,188,751 issued June 27, 191.6. Molds of this kind are usually supported on a stool or supporting plate during the pouring and solidification of the ingot and such tools have heretofore usually been provided with a short projection, which entered the opening in the bottom of the mold. Such a projection, as shown in my U. S. Patent No. 1,019,244 issued March 5, 1912, has heretofore been used for centering the mold on the stool and for assisting in preventing lateral finsfrom forming between the horizontal bottom of the mold and the upper horizontal face of the stool. Slurry or other sealing device has usually been applied in the annular opening between the inner mold walls and the outer walls of the said projection to insurea perfect seal.

The object of my present invention is to not only elliciently seal the bottom portion of the mold chamber, but to so construct the stool that the initial impact of the steel asit is bein teemed into the mold will be received wit 'n a recess located in the stool which recess constitutes a part of the mold chamber.

In this class of molds, known as the bigend-up type, where the mold is usually made in one vertical piece, it is necessary in strip ping the ingot from the mold to lift it therefrom or to push it upwardly out of the mold. llf molten metal leaks from the bottom of the mold in such a manner as to form a lateral fin at the junction of the mold and the stool, the stripping of the ingot 'is prevented or made difficult. Furthermore, if the walls of the mold cavity are not properly formed, the ingot frequently sticks or binds to the lower part of the mold, which further impedes or prevents the stripping operation. Therefore, it is important that the mold cavity should be free from reentrant angles whichv would tend to impede the stripping operation or the removal of the ingot from the mold.

According-to my present i'nventioml employ a separable stool which, instead of having a projection adapted to enter the mold ters approximately with the bottom opening of the mold. In order to assure of this recess or cavity approximately registering bottom opening and with said ledge.

arrangement is such that the formation of imwith the bottom opening of the mold, the stool is formed with a bead or ridge, which by contact with the outer lower vertical walls of the mold centers the mold on the stool in such a manner that the bottom to opening of the mold will always be, properly located with reference to the recess or cavity in the stool. The width or diameter of the recess or cavity in the stool at its upper edge is somewhat less than the width ores and the ledgethus surrounds the recess in to the stool. On: this ledge a collar or gasketof suitable sealing material may be fitted to contact with the vertical walls of the mold The this on the ingot bottom edges, such as would be produced by lateral leakages under the bottom of the-mold when seated on stools of the old type heretofore known in the art,

isnecked-in or inclined downwardly and inas wardly towards a bottom opening, and 1- preferably employ refractory shrink head casings or feeders fitted to the upper part of the mold chamber to centralize the pouring of the molten metal metal as well as to assist in preventing or reducing the formation of pipe in the solidifying ingot. The

shrink head casing or mold top is preferably considerably less in interior diameter than the diameter ofthe mold chamber at its lower end where-the necked-in portion commences, so that in pouring the ingot the narrow stream of liquid steel will not im-. pinge against the vertical mold walls.

My improvements are illustrated in the accompanying drawings, in which Figure 1 is a vertical central section through a mold, its stool and its shrink head casing.

Figure 2 shows a section on the line 2-2 50f Figure 1. cavity, has a recess or ca'vlty which reg1s- Figure 3 is a sectional view on an enlarged scale of the stool and the lower portion of the mold.

V The mold A rests'on a stool B, which is 1110 of novel construction, the details of which will be hereinafter described. The stool is formed with a ridge or bead b on its upper face, which is preferably shaped-as shown in Figure 2 and is preferably continuous although the bead I) need not necessarily be of a continuous formation. This head of ridge 6 serves to locate the mold base and thus center the bottom opening of the mold chamber in its relation to the recess 6 located in the stool when the mold is seated upon the stool. The recess or cavity b is formed in the upper side of the middle portion of the stool and is of a smaller diameter than the diameter of the lower end of the bottom opening of the mold. For instance, if the diameter of the bottom opening of the mold is the diameter of the top of the cavity in the stool should preferably be about 18'', or at least sufficiently less than the diameter of the bottom opening in the mold so that when the mold is seated on the stool, being located in this seating by the ridge or bead b,

a ledge 00 will be formed within the walls ofv the bottom opening of the mold, said ledge m then surrounding the cavity or recess in the stool. Sealing material an of any suitable kind may be fitted to seat on this ledge and contact with the inner walls of the bottom opening of the mold, but such sealing material is not always necessary.

The relative dimensions employed for different parts of the mold and stool are those "preferred and to carry out my invention to the best advantage, are preferably, approximately such as indicated on the drawings.

Particular attention is called to the factthat the diameter of the bottom opening of mold chamber is larger than the diameter of the top of the stool recess for the purpose herembefore mentioned. As indicated in Figure 3 of the drawings. when the width of the mold at its lower end or bottom portion is 42", the diameter of the space between the beads or ridges on the stool is preferably as shown 43", approximately 1" clearance being allowed as a margin for seating the mold base on the stool. This margin may be somewhat less or somewhat more, but the relative dimensions of the base of the mold and the space between the beads or ridges on the stool must be such that when the mold base is seated on the stool between the ridges or beads thereon, there will always be a ledge .90 surrounding the recess 6 in the stool even through the mold is shifted sidewise so that its lower vertical walls bear against one or another of the inner faces of the ridge or bead of the stool.

It is highly desirable in my construction that the base of the mold and the upper face of the stool be made smooth by machining or other means so as to insure a smooth unbroken contact between the mold bottom and the upper face of the stool.

When such a mold is mounted on a stool constructed as shown, there is small chance for lateral leakage of any molten metal and consequent fin formation. To prevent 1111- due wear of the ledge of the stool and of the bottom of the mold chamber walls, I may employ sealing material of any desired kind and shape and apply it at the junction of the inner walls of the mold bottom and the annular ledge w of the stool.

Due to the recess in the stool, the ingot will be formed with a projection extending below the bottom of the mold A, so that when the mold is lifted from the stool B. the ingot may be loosened from the mold walls by merely lowering the mold with its contained ingot onto an abutment o'r suit; able stripping device, which will engage tht projection and thus lift the ingot in the mold suflicie-ntly to loosen it from the mold walls in case it should tend to adhere thereto. The ingot can then be entirely removed from the mold by suitable tongs or other appliance engaging the up er end thereof, in a manner shown in my S. Patent No. 1,059,668 of April 22, 1913.

The shrink head casin C is preferably made of refractory material and is adapted to enter the upper portion of the mold cavity, as shown. Its interior diameter is considerably less than the diameter of the greater portion of the mold cavity andis approximately the same as or less than the bottom opening of the mold. By this construction, when the narrow stream of molten metal is poured into the mold the side walls of the mold cavity will be protected, the impact of the metal being confined to the stool and particularl to the chambered part of the stool. en the stool is worn away or impaired it may be readily replaced by another for use with the same mold at comparatively small cost. Thus by employing a chambered stool of the kind shown in connection with a neckedin'mold of the sortillustrated and with a shrink head casing of the construction described I am enabled not only to prevent injury tothe mold walls while pouring but I prevent the formation of fins at the bottom of the mold which would impede the stripping of the ingot from the mold and I facilitate the stripping operation by reason of the necked-in contour of the mold cavity and by the formation of a projection on the lower end of the ingot which extends below the bottom of the mold.

I claim as my invention:

1. A metallic mold provided with an ingot-forming chamber open at top and bottom having a necked-in portion above the bottom opening and merging thereinto, in

combination with a mold stool having a recess 1n communlcation with said necke -in portion and WlllCh recess is surrounded by h miw an unbrokeimledge for supporting sealing i'omflod by an unbroken ledlge and a ring materials. V- of sealiiig material resting on said. lodge 2. A motallic molcl provided with an and making coniacl; with the side walls of w ingot forming chiimlbei' open at top andbotthe bottom oning of the mold. 5 tom, in combination with a mold stool hav- In testimony whereof, l have hereunto inga recess in oommunication with tho bola-o subscribed my name. tom opoiii of the mold which recess is sur- EL GATHNN 

